The number of grams of radon 222 did it have 15.2 ago was 49.6 grams( answer C)
<u>calculation</u>
- calculate the number of half life it has covered from 15.2 days to 3.8 days
that is divide 15.2/ 3.8 = 4 half life
- half life is time taken for a radio activity of a specified isotope to fall to half its original mass
therefore 3.8 days ago it was 3.1 x2 = 6.2 grams
7.6 days ago it was 6.2 x2 = 12.4 grams
11.4 days ago it was 12.4 x2= 24.8 grams
15.2 days ago it was 24.8 x2=49.6 grams
Answer : The most likely happens during this reaction is, Oxidation-reduction
Explanation :
The balanced reaction will be,
In this reaction, neutral iron loses 3 electrons and oxidizes in (+3) state, 
and neutral oxygen gains 2 electrons and reduces in (-2) state,
When iron react with oxygen gas to give iron oxide. This process is known as iron rusting. During the reaction, oxidation-reduction process occurs.
Oxidation : It is a type of chemical reaction in which a substance loses its electrons. Or we can say that in oxidation, the oxidation number increases.
Reduction : It is a type of chemical reaction in which a substance gains its electrons. Or we can say that in reduction, the oxidation number decreases.
Answer:
The area of vegetable garden is 16.422 m².
Explanation:
Given data:
Length = 4.83 m
Width = 3.4 m
Area = ?
Solution:
Formula:
Area = length × width
Area is measured in square unit.
By putting the values in formula:
Area = length × width
Area = 4.83 m × 3.4 m
Area = 16.422 m²
The area of vegetable garden is 16.422 m².
Answer is: <span>functional groups.
</span>Functional groups<span> are specific </span>groups<span> that are responsible for the characteristic chemical properties of molecule.</span>
<span>Proteins have nitrogen and oxygen in functional group.
Nucleic acids and some lipids have phosphorus in fuctional group.
Carbohydrates have oxygen in functional group for example.</span>
